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PolarStar A&K SR25 Installation Spacer Adapter Kit for Fusion Engine

ID: 53551 (PS-ISK)
PolarStar A&K SR25 Installation Spacer Adapter Kit for Fusion Engine
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  • Convert your standard Ver2 Fusion Engine to be compatible w/ Ver2 Extended receivers (such as SR-25 rifles)
The A&K SR-25 Spacer Kit comes with a delrin spacer which gets pressed into the front of the Fusion Engine's cylinder to make the Version 2 engine the same length as the original extended Version 2 gearbox used in the rifle. Also included is a M5x0.8mm nut which is placed inside the rear of the lower receiver for the stocks bolt to thread into instead of the rear of the engine. This kit coupled with the A&K Masada Nozzle (purchased separately) allows the engine to interface with the rifles original M4 type hop-up chamber.

Application: Mounts to front of PolarStar Fusion Engine. Requires A&K Masada Nozzle.
Compatibility: For Version 2 PolarStar Fusion Engines
Material: Delrin, Steel

Manufacturer: PolarStar

About PolarStar

PolarStar Precision Airsoft was formed in January 2009 to fill a need for high quality, precision manufactured airsoft components designed for performance and longevity.The 2011 release of the patented Fusion Engine HPA system marked a change in direction for PolarStar. The focus shifted from developing upgrade components within the constraints of existing systems to developing innovative HPA systems and accessories which replace the aging AEG technology.PolarStar Airsoft is a division of PolarStar Engineering & Machine (PSE&M), a unique blend of tenured American toolmakers and a full service CAE/CAD/CAM (Computer Aided Engineering, Design, and Manufacturing), special crafts machine shop keeping alive our proud manufacturing heritage of Made in the USA. Founded in 1997, PSE&M began by servicing the automotive racing industry through the design and producing systems and components from art to part. Operating under the auspices of the Delaware Association of Professional Engineers, we retain a Professional Engineer (P.E.) on staff to ensure and certify all design and engineering standards are met. In addition to our own product line, PolarStar also offers engineering and manufacturing services tailored to the airsoft industry.

1 Customer Review

(Write a review)

by Anthony F. on 05/02/2023
"Fit in my Matrix SR25K with a fusion engine and runs like a dream.

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